MathDB
Inequality with gcd

Source: Russian TST 2020, Day 6 P2

March 21, 2023
number theoryinequalitiesgreatest common divisor

Problem Statement

Given a natural number nn{} find the smallest λ\lambda such thatgcd(x(x+1)(x+n1),y(y+1)(y+n1))(xy)λ,\gcd(x(x + 1)\cdots(x + n - 1), y(y + 1)\cdots(y + n - 1)) \leqslant (x-y)^\lambda, for any positive integers yy{} and xy+nx \geqslant y + n.